Engine



N. PAVIA AND G. CASALIS. OSCILLATING PISTON ENGINE- APPLICATION FILED MAR- 24|' I915.

Patented Oct. 7, 1919.

WITNESSES A TTORNEYS nmummml cm, WASIIINI'ITL NICOLA PAVIA AND GIACOMO CASALIS, OF TURIN, ITALY.

. osornnn'rrne-risron ENGINE.

Specification of Letters Patent.

Patented 0a. 7, 1919.

Application filed March 24, 1916. Serial No, 86,451.

To all whom it may concern:

Be it known that we, NICOLA PAVIA and GIACOMO CAsALIs, residing at Turin, Italy, have invented certain new and useful Improvements in Oscillating-Piston Engines, of which the following is a full,'clear, and exact specification. r

The invention relates to oscillating piston engines and has for its object to produce such an engine which is compact, simple, inexpensive and durable.

Figures 1 and 1 show schematically the principle of the invention, Fig. 2 shows a manner of practical application of the same to an internal combustion two stroke engine; Fig. 3 shows the diagram of the distribution and controlling of a complete working operation with the angular phase displacements with reference to the diflerent positions of the crank.

Referring to the drawing A is the closed case in which two pistons B are hinged to the hollow pin 1), said pistons being con nected by means of the jointed rods 79 to the crank pin 0 of a rotatable shaft C. During the rotation of shaft C the pistons B take the end position shown on the drawing, wherein in Fig. 1 they are schematically shown by means of triangles coming nearer to and farther from each other. Under the action of a motive fluid acting by a static or dynamic pressure, the pistons B take an alternative circular motion of a convenient extension, as to the degree of expansion and compression wanted while the crank pin 0 receives a rotating continuous pull.

At the end of the work the advance of.

the left hand piston to the right hand one, permits the opening of the exhaust port 9 leading from the chamber at the side of the case through the side thereof, as shown in Figs. v1 and 1 or 9 leading through the peripheral wall of the case or casing A before the opening of the port 10 leading from the chamber at the side of the case through the side thereof, as also shown in Figs. 1 and 1 or 10 leading from the crank casing or compression chamber to the cylinder or interior of the'case through the ports 10 for the admission of the new fluid, while by the displacement of the crank pin from the position 11 to 12, as shown in Fig. 1, the left hand piston is lifted and shuts the port 9 or 9, and the right hand one still lowers itself and opens the port 10 Or 10', and admits the motive'fiuid, which had been previously sucked from a and compressed in the tight chamber 13, integral or formed separately. The pistons B with their members 15 are sector shaped and contact with the case A and control the distribution. An internal combustion two stroke engine is thereby obtained, as shown on Fig. 2. The pressure of the compressed mixture and that of the gases pushes the edges which may be flexible, against the case A making a tight joint; to this end helping also the natural dilatation of the piston on account of the increases in temperature due to the compression and explosion phases.

The peripheral edges extend in the sec tions 15 so that they are .at'the same time a controlling guide of the motion and a controlling means for the distribution in the different working phases.

F ig. 3 shows the working cycle of the engine, the direction of rotation being shown I by the arrow P.

The mixture admitted between the pistons in a volume V, is compressed and reduced to the volume v; the vanes, the rod pins and the crank pin on the shaft are then in the position 1. At this moment the ignition of the compressed mixture 'v is produced in any known manner; the pistons move farther apart until the whole system takes the position 4. On the whole are d the expansion takes place.

The left hand piston begins to open the port 9 and the exhaust period begins on the whole are e. In the meantime the right hand piston having arrived at the point 3, the opening of the port 10' begins by which the new mixture enters. During the are 7' there will be scavenging and exhaust; during the are 9 the port 9 being closed and the port 10 open, the pure charge is admitted, that is to say the volume V of the mixture enters between the vanes and during the stroke on the are 72, is compressed to the volume 'v, and then the phases referred to repeat themselves. During the compression h the new mixture is sucked from the outside through the valved which during the expansion dis-compressed in the tight chamber 13 because the valve a is closed again for the purpose of having the mixture ready to flow rapidly into the engine as soon as the port 10 is opened and scavenge all the burnt gases, clean the ch m er and make a new and pure charge.

In this engine no residual of the burnt gases remains in the engine; the charge is pure and not so high in its temperature not being mixed with residual gases; a long expansion is permitted; the distribution is made by the pistons without any valve or supplementary organs under control; there is work at every rotation with a succession more regular in the efforts of rotation given to the crank of the shaft. It is to be understood that a cooling fluid circulates outside of the case of the engine, the fluid entering by the way of the hollow pin 6 and so that the coolingfluid reaches the center of the engine.

Referring to Fig, 3 which shows the working of the device, when the crank pin is at the point -3 of its rotation, the left hand piston is at the top of its stroke, while the right hand one has still to pass from 3 to 1, that is to say its connecting rod has still a speed which produces on the crank pin the tangential component 3 which transfers the crank pin in 2. There the left hand piston being lowered, and the right hand one still lifting, the connecting rods have opposite speed,so that two tangential components 2 2 act on the crank pin having the same direction and producing the displacement of the latter.

By means with a suitable connection of the center pin 6, which may be either obtained by a pressure fluid or by mechanisage leading from the compression chamber to the' inlet port of the piston chamber, pistons pivoted in the piston chamber on a common pivot and between which the combustible mixture is admitted through the inlet port of said piston chamber, one of said pistons controlling the exhaust port and the other controlling the inletport, a crank shaft in the compression chamber, and links connecting the pistons with the crank shaft, the links being pivoted directly to the pistons.

In witness whereof, we have hereunto signed our names in the presence of two subscribing witnesses.

NICOLA PAVIA. GIACOMO GASALIS.

Witnesses ANDREA LUINO, ROGER C. TREDWELL.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents,

Washington, D. 0. 

